Lightheaded when lifting above my head?

I'm a little concerned because I have an ongoing issue that when doing any sort of lifting above my head while standing (say, a standing shoulder press), I get lightheaded very easily. I don't think it's a breathing issue since I watch that closely (and that would be obvious answer), but even today just doing 10lb (!) dumbbells as a warmup (I'm doing the week-1 on the workouts from Realjock, this would be the rotating shoulder exercise), I'd get to about 10 of 15 and just feel like the blood was draining from my head.

I don't get affected doing any other exercises (at least not so far), I can do a hour of bike riding no problem, sitting and doing cable pulls no problem.. bench press, pushups whatever.. it's really just the standing with raised arms.

Is this just a result of being a beginner to weightlifting, a lack of oxygenated blood because my body's making a choice between my arms and my head? It's kind of freaky. At least once I stop and if I sit down, it clears up relatively quickly (60-90 seconds usually).

This seems pretty strange...one thought that immediately comes to mind is subclavian steal syndrome in which bloodflow is routed to the arm at the expense of the brain...this occurs due to a proximal occlusion of the subclavian artery so that it must obtain bloodflow form the vertebral artery which supplies the posterior part of the brain....this is very rare and usually occurs in people >55 with atherosclerosis so it is highly unlikely that this is the actual cause of your symptoms....I would guess your symptoms are related to being a beginner weightlifter but I would still get checked out by your family doc if the symptoms continue.

With any strange syndrome that occurs with any regularity my first advice is to go get it checkedas someone had said before me - the worst case scenario is a situation where the blood flow to the brain is being temporarily slowed or cut offthe brain is extremely sensitive to any lack of oxygenation and if it's long term can lead to permanent damagetalk to your doc

If it's any consolation, I experience the same thing and have for years. Even stranger, it seems to be mostly limited to the overhead upward-press type of exercise (I can do lat pull-downs without a problem). As a result, I am much more cautious with these types of exercises and make sure I quit at the first signs of light-headedness.

It sounds like you're going hypotensive. Ongoing lifting should help with your vascularization, particularly if you haven't been an active person in the past. You also may be low on fluid, literally, if you've been doing some sort of diet pill (your profile indicates weight loss).

Fainting is your body's response to low blood pressure on want to get your head at the level of your heart.

Poor cardiovascular tone (it's called) is usually seen in young, sedentary, women. I used to work as a phlebotomist and we'd have them go low all the time. They'd have low fluid, low calories, and be out of shape. Out like a light.

Check with a doctor. They almost certainly have a specific test to tell what's going on.

Slow down on your workouts. If you've been inactive, understand...it took years for you to get in such a mess, and you won't fix it overnight.

so, i'm glad that you posted this, as i have the same issue. i have been diagnosed with vasovagal syncope (VVS). VVS is a neurological and cardiovascular disorder, wherein your vascular system cannot adequately respond to changes from various variables. the response, which most likely ends in a drop in heart rate and blood pressure (hypotension), and possibly fainting. for me, i mostly get extremely lightheaded, tunnel vision until everything goes black, and i also "see stars." several times, i have indeed fainted. triggers of a vasovagal episode include fatigue, stress, hunger, high temperature, and most commonly changes in altitude (e.g. sitting or standing up), among others. however, i've noticed that when i lift my arms above my heart, i get a similar response.

to control this, i have been taking an SSRI antidepressant, celexa to be specific, for the past six months, and it seems to have cut down the frequency of episodes. however, make sure you drink plenty of water, increase your salt intake (to retain fluid in your bloodstream, just in case you are also hypovolemic [low blood volume]), and to get plenty of rest before you exercise. but, i'd go see your doctor to get a referral to a cardiologist so you can be adequately tested. one thing you can do preliminarily, is to lay down flat at home for 5 minutes (to let your blood pressure normalize), take your pulse (and blood pressure, if you have a cuff and know how to do it), then stand up quickly, and take your pulse (and pressure) again. you're looking for a drop in your pulse and pressure. your physician can also do this in his/her office just to get an idea of whether you may have VVS, before getting a tilt table test.